Nozzle



1950 B. R. WALSH 2,961,171

NOZZLE Filed Dec. 24, 1958 IN V EN TOR.

BRUCE R. WALSH ATTORNEY United NOZZLE Filed Dec. 24, 1958, Ser. No.782,917

6 Claims. (Cl. 239-465) The present invention relates to new and usefulimprovements in high-pressure, gun-type burner nozzles, and moreparticularly pertains to a gun-type burner nozzle provided with asubstantially spherical, swirl-imparting and distributing member withmeans to secure precise positioning and alignment thereof, together witha cooperating discharge orifice characterized by the stabilization offuel fiow rate despite varying fuel viscosities.

The present invention is related to that disclosed in my similarlyassigned application entitled Apparatus (Case A) filed concurrently withthis application, and particularly in that the swirl stem and theassociated air passageways disclosed therein or a conventional swirlstem can be employed in the nozzle of this invention, if desired, inlieu of the sphere-like distributing and swirling means hereinafterdisclosed.

In general, the present invention is concerned with securing precisealignment of distributing elements that are at least spherical in partsuch as disclosed in US. Patent No. 2,07l,920 to Czarnecki to realize asymmetrical vortex of fuel flow in the swirl chamber and to make therate of fuel fiow by the distributing element less susceptible tochanges in fuel viscosity. The invention is also concerned withdischarging the symmetrical vortex of fuel flow in the swirl chamber asa symmetrical conical spray pattern at a rate relatively unafiected bythe viscosity of the fuel. Also, the invention is concerned with theprovision of a nozzle of reduced susceptibility to coking, particularlyin such critical locations as the discharge orifice and in the slotsthrough which a swirling motion is imparted to the fuel.

Broadly, the invention involves the provision of a swirl chamber thathas a fiat wall at the inlet end of the discharge orifice, with thedischarge orifice including a cylindrical section of a length notgreater than its diameter that defines a sharp-edged right angle withthe fiat wall of the swirl chamber. Another aspect of the inventionincludes means for mounting a distributing member having a sphericalsurface in exact alignment and engagement with the tapered internalsurface of the nozzle body. Such mounting means includes provision forpermitting sufficient transverse freedom for the distributing member sothat the latter can seat properly while preventing rotation of suchmember about any axis transverse to the central axis of the nozzle.

The invention will be best understood 'upon reference to theaccompanying drawings illustrative of preferred embodiments thereof,wherein Figure 1 is a fragmentary side view of the gun-type nozzle, withthe nozzle body being shown in central section, and wherein Figure 2 isan enlarged detail view partly in section of a modified mounting meansfor the distributing member.

Referring to Figure l, the numeral designates a hollow nozzle bodyexternally threaded at 12 for threaded connection to a fuel supplyconduit 14.

The nozzle body 16 is provided with an internal frustoconical surface 16against which is seated a distributing member 18 establishing a line ofcontact 19 between the rates Patent member 18 and the nozzle body 10.The member 18 is spaced from the nozzle body 10 and the internalconfiguration of the nozzle body 10 is such that a swirl chamber 20,preferably of cylindrical configuration, is defined. The end of theswirl chamber 20 remote from the member 18 is defined by a flat wall 22normal to the central axis of the nozzle body 10.

A discharge orifice 24 is provided for the swirl chamber 20. Thedischarge orifice 24 includes a cylindrical section 26 that iscoincident at its inlet end with the fiat wall 22 to define asharp-edged right angle 28. The cylindrical section 26 of the dischargeorifice has an axial length that is not greater and preferably less thanits diameter.

The distributing member 18 presents a spherical surface toward the swirlchamber 2il, and such spherical surface extends rearwardly from theswirl chamber 20 for a substantial interval beyond the line of contact19 to such an extent that the spherical surface constitutes at leastabout a hemispherical surface and can be to such an extent as toconstitute the major portion of an entire spherical surface.

Mounting means are provided for the distributing member 18 such as toassure a line of contact, indicated at 19, seating of the member 18, andto prevent rotation of the member 18 about any axis transverse to thecentral axis of the nozzle body 143. Such means comprises an insertelement 32 screwed, as at 54, into the nozzle body 10. The insertelement 32 is provided with a kerf 36 for tool use in screwing theinsert element into the nozzle body 10. Also, the insert element 32 isprovided with a central blind bore 38 that communicates with atransverse opening 40 so that fuel can pass through the insert element32 from the conduit 14 to the member 18. The end of the distributingmember 18 remote from the swirl chamber 20 terminates in a fiat surface42 that engages a flat end of a stud 44 forming a part of the insertelement 32, with such engagement being only on a plane normal to thecentral axis of the nozzle body 10.

The distributing member 18 is provided with a plurality ofcircumferentially spaced swirl slots 46 that extend across the line ofcontact 19 which are inclined thereto as clearly shown in the drawing.In lieu of the slots 46 being provided in the member 13, slotscorresponding thereto can be provided in the nozzle body to extendacross the line of contact in inclined relation thereto. This isillustrated in Figure 3 wherein slots 70 are provided in the nozzle bodyto extend across the line of contact between the member 72 and thenozzle body 74 in inclined relation thereto.

The operation of the nozzle shown in Figure 1 will be easily understood.Fuel is introduced into the interior of the nozzle body 10 underpressure from the conduit 14 through the blind bore 38 and the tranverseopening 46. The fuel so introduced enters the swirl chamber 20 at a highvelocity through the swirl slots 46 with a swirling motion, thencepassing from the swirl chamber through the discharge orifice 24 as aconical spray.

The nature of the engagement of insert element 32 with the member 18allows precise seating of the member 18 against the frusto-conicalsurface 16, and leakage of fuel between the frusto-conical surface andthe member 18 other than through the slots 46 is avoided. The engagementof the insert element 32 with the member 18 allows transverse movementof the member 18 so that precise seating thereof is realized even withslightly imperfect alignment of the insert element 32. This is importantas machining of parts capable of perfect alignment of an insert memberis a goal difiicult of consistent achievement. Leakage of fuel due toimproper seating is conducive to coking and can also impair the spray byunbalancing the swirling action given the fuel in the swirl chamber 20.

Since the fuel is constricted to flow essentially solely in the slots 46for a very short distance in the immediate vicinity of the line ofcontact 19, the rate of fuel flow is relatively unaffected by changes infuel viscosity as compared to lengthy slots in which fuel is constrainedto how. Also, such reduced length of constricted flow lessens thelikelihood of coking obstructing the flow of fuel in the slots 46. V

The sharp-edged right angle 28 defined between the flat surface 22 andthe cylindrical section 26 of the discharge orifice 24 coupled with thelength of the cylindrical section 26 being less than its diameter isvery important in the operation of the nozzle in that a venturi-shapedflow will take place in such cylindrical section 26 such that viscouscontact of the fuel with the sides of the cylindrical section 26 issubstantially reduced, whereby the rate of fuel discharge therethroughis to a substantially corresponding extent unaffected by fuel viscosity.Also, such lack of viscous contact of the fuel with the sides of thecylindrical section 26 minimizes the likelihood of coking in suchsection 26 as well as minimizing the deleterious effects of any cokingthat might occur therein.

In Figure 2, there is illustrated a modified structure for assuringproper seating of the distributing member 18.

'Thenumeral t} designates a substantially spherical distributing memberthat corresponds to the member 18 of Figure 1. The member 50 is providedwith slots 52 that correspond to the slots 46 of Figure l. The numeral54 designates an insert element that corresponds to the element 32 ofFigure l, and in a similar manner the insert element 54 includes a stud56. The stud 56 terminates in a centrally positioned frusto-conical tip58 that is received in a frusto-conical recess 60 provided in thedistributing member 56. As shown, the transverse dimensions of therecess 66 are greater than the transverse dimensions of the tip 58, sothat a limited lateral freedom for the member 50 relative to the tip 58is permitted. Preferably, the tip 58 has a length sufficient to seatagainst the bottom of the recess 60 and, in order to insure lateralfreedom, such contacting is only over a surface whose plane is normal tothe central axis of the nozzle body. If desired, the flat surface 62 ofthe stud 56 can contact the member 50 about the base of the tip 58.

The illustrated embodiments of the invention are susceptible to numerousvariations without departing from the spirit ofthe invention. Asexamples of minor departures of such character is tapering the interiorof the nozzle body to only approximate illustrated frusto-conicalsurface 16; giving the swirl chamber 20 a frusto-conical configurationwhile preserving the fiat wall 22 rather than the illustrated generallycylindrical configuration; and lapping the member 18 with the nozzlebody to slightly widen the line of contact 19. Obviously, the nozzlebody 10 need not be an integral body, but of joined component parts.Accordingly, attention is directed to the appended claims in order toascertain the actual scope of the invention.

I claim:

1. In a gun-type burner'nozzle, apparatus comprising a hollow nozzlebody having a central axis, the interior of the nozzle body having agenerally frustoconical surface adjacent to and tapered toward one endof the nozzle body, a distributing member disposed within the nozzlebody and seated against the internal frusto-conical surface of thenozzlebody, means defining slots intermediate the seated portions of thedistributing member and the nozzle.

body for imparting a swirling motion to fuel passing through the slotstoward said one end of the nozzle body, said distributing member beingspaced from said oneend of the nozzle body to define a swirl chambersymmetrical about the central axis for receiving swirling fuel from theslots, said nozzle body having a flat internal surface normal to thecentral axis defining the end of the swirl chamber remotefrom saiddistributing member, and said nozzle body having an axial dischargeorifice in said one end thereof that communicates with the swirlchamber, said discharge orifice including at least in part a section ofcylindrical configuration having one end coincident with said flatsurface to define a sharp-edged right angle at the intersection of thedischarge orifice with the swirl chamber, said cylindrical section ofthe discharge orifice having an axial length not greater than thediameter thereof.

2. The combination of claim 1, wherein the swirl chamber has acylindrical configuration adjacent the discharge orifice.

3. In a gun-type burner nozzle, apparatus comprising a hollow nozzlebody having a central axis, the interior of the nozzle body having agenerally frusto-conical surface adjacent to and tapered toward one endof the nozzle body, a member disposed within the nozzle body having atleast in part a spherical configuration, said member presenting aspherical surface toward said one end of the nozzle body, means forpositioning and also holding the member so that the spherical surfacethereof is seated by substantially a line of contact against theinternal frustoconical surface of the nozzle body, means for preventingrotation of the member about any axis inclined to the central axis, saidmember having a plurality of slots therein that are circumferentiallyspaced along said line of contact with such slots being inclined to andextending across said line of contact, said member being spaced fromsaid one end of the nozzle body to define a swirl chamber symmetricalabout the central axis, said nozzle body having a fiat internal surfacenormal to the central axis defining the end of the swirl chamber remotefrom said member, and said nozzle body having an axial discharge orificein said one end thereof that communicates with the swirl chamber, saiddischarge orifice including at least in part a section of cylindricalconfiguration having one end coincident with said fiat surface to definea sharp-edged right angle at the intersection of the discharge orificewith the swirl chamber, said cylindrical section of the dischargeorifice having an axial length not greater than the diameter thereof.

4. The combination of claim 3, wherein said means for positioning andholding'said member includes an insert element threaded in the nozzlebody, said insert element carrying a stud that extends toward saidmember, said means for preventing rotation including said member and thestud having only flat surfaces in engagement on a plane normal to thecentral axis.

5. In a gun-type burner nozzle, apparatus comprising a hollow nozzlebody having a central axis, the interior of the nozzle body having agenerally frusto-conical surface adjacent to and tapered toward one endof the nozzle body, a member disposed within the nozzle body having inpart a spherical configuration, said member presenting a sphericalsurface toward said one end of the nozzle body, the spherical surface ofsaid member engaging the internal frusto-conical surface of the nozzlebody upon substantially a line of contact, said member having aplurality of slots therein that are circumferentially spaced along saidline of contact with such slots being inclined to and extending acrosssaid line of contact, said member being spaced from said one end of thenozzle body to define a swirl chamber symmetrical about the centralaxis, said nozzle body having an axial discharge orifice in said one endthereof that communicates with the swirl chamber, and an insert elementthreaded in the nozzle body, said insert element carrying a stud thatextends toward said member, said stud having a flat surface, said memherhaving a corresponding flat surface, the only surfaces of contactbetween said stud and said member being the flat surfaces on a planenormal to the central axis whereby said member can move laterally withrespect to said stud during positioning.

6. In a gun-type burner nozzle, apparatus comprising a hollow nozzlebody having a central axis, the interior of the nozzle body having agenerally frusto-conical surface adjacent to and tapered toward one endof the nozzle body, a member disposed within the nozzle body having inpart a spherical configuration, said member presenting a sphericalsurface toward said one end of the nozzle body, the spherical surface ofsaid member engaging the internal frusto-conical surface of the nozzlebody upon substantially a line of contact, the internal frusto-conicalsurface of the nozzle body having a plurality of slots therein that arecircumferentially spaced along said line of contact with such slotsbeing inclined to and extended across said line of contact, said memberbeing spaced from said one end of the nozzle body to define a swirlchamber symmetrical about the central axis, said nozzle body having anaxial discharge orifice insaid one end thereof that communicates withthe swirl chamber, and an insert element threaded in the nozzle body,said insert element carrying a stud that extends toward said mem her,said stud having a fiat surface, said member having a corresponding fiatsurface, the only surfaces of contact between said stud and said memberbeing the flat surfaces on a plane normal to the central axis wherebysaid member can move laterally with respect to said stud duringpositioning.

References Cited in the file of this patent UNiTED STATES IATENTS1,259,052 Starr Mar. 12, 1918 2,071,920 Czarnecki Feb. 23, 19372,107,601 Davis Feb. 8, 1938 2,562,731 Murphy July 31, 1951 2,566,532Olson Sept. 4, 1951 2,607,193 Berggren Aug. 19, 1952

